On April 29, 2002, the newly confirmed NASA Administrator Sean O’Keefe planted a time bomb in the International Space Station program. Coming to NASA from the US Office of Management and Budget, where he was Deputy Director, Mr. O’Keefe had a reputation as a bean counter and penny pincher. Mr. O’Keefe publicly joked that he was not smart enough to be NASA Administrator. But he knew the ISS program needed political capital in the US political arena. Providing a big, flashy cut in the ISS program would cement O’Keefe’s position as NASA Administrator and aid in the annual budget fights in the US Congress. One part of the ISS program caught his attention: the plan to develop a US “lifeboat” for the ISS. Since the Russian Soyuz could fulfill that job – and the Russians were providing that service as part of their initial contribution to the international partnership – the Crew Rescue Vehicle (CRV or X-38) became an easy cut. So on April 29, the total dependence on the Soyuz for the life of the ISS program was established by NASA fiat, with virtually no consultation with the other ISS partners.
Flash forward nearly a decade: with the ISS construction completed, the incredibly capable but ever risky NASA Space Shuttle is retired. Not that the Shuttle could have replaced the Soyuz; Shuttle stays at the ISS were limited to about two weeks duration, not the six or more months an expedition crew stays aboard. The logistics is not the problem: cargo and logistical resupply can be accommodated by the European Space Agency Automated Transfer Vehicle (ATV), the Japanese H-II Transfer Vehicle (HTV), two new cargo vehicles under development by the US commercial space industry – the Orbital Science Corporation Cygnus cargo vehicle launched on their Taurus–II launch vehicle, and the Space Exploration Technology’s Dragon capsule launched on their Falcon 9 rocket. And, of course, the old reliable Russian Progress cargo vehicle.
The Progress rides the same basic rocket as the Soyuz spacecraft. Soyuz is now the only way to transport human beings to and from the ISS. New spacecraft are being developed to provide future human transportation to the ISS. Boeing, SpaceX, Blue Origin, and Sierra Nevada are competing for US government development funds to build human transportation vehicles within the next 5 years.
But Mr. Murphy, the author if the law that states “if anything can go wrong, it will,” struck on August 24, just one month after the Shuttle was retired. The third stage of the Russian launch vehicle suffered a critical failure and the 44th Progress resupply vehicle to the ISS broke up and crashed in eastern Russia. A state commission has concluded that the failure was a random one and that reinspections of the existing launch vehicles could clear them for early flight. Time will tell, the Russians know their business well and I expect them to be successful.
The implication is clear. The O’Keefe time bomb is on short fuse. If the Soyuz cannot fly safely, then the ISS will lose its human crew – and its reason for existence. Until there is another craft that can not only carry human beings back and forth from the ISS but also stay there with them for six months as a life boat, the ISS is on shaky footing. Not that the Russians are unreliable or their launchers are not dependable – quite the opposite. But in the world of space flight, random failures do occur. Even if the shuttle were still in service to carry human beings to the ISS, that would not be sufficient to keep the ISS staffed; the shuttle could only stay in flight for two to three weeks – not the six months required for the lifeboat function. When will the Dragon, the Dreamchaser, or the CST-100 be ready to carry people and serve as a lifeboat? Not soon enough.
We could have really used that CRV. It might even have become the basis of a mini-shuttle crew transport vehicle. But no; it was eliminated for the most transient and banal of reasons. The old adage against being “penny wise and pound foolish” has struck the human space effort once again.
Or more to the point; every good space designer knows that a system with a critical single point failure is not a good system. Reliability is key, but even then, having redundancy is the standard practice for a truly resilient system.